ST. LOUIS–(KMOX)–If they wrote blues songs about the coal industry, they’d have plenty to sing about — as three major coal companies in St. Louis are under pressure from falling demand, tougher regulations and competition from natural gas.

Peabody Energy, Arch Coal and Patriot Coal have all seen their stock values fall near 52 week lows and there’s no let up in sight.

“Near term, there are a lot of uncertainties over how bad the economic downturn is going to be in Asia,” said Marketwatch.com Energy Reporter Steven Gelsi, “and what the regulatory environment is going to be here in the United States and if Obama loses the election that could have an effect on the EPA’s move to regulate emissions.”

In March, the Obama Administration unveiled plans to limit carbon dioxide emissions from new power plants, after a 2007 Supreme Court ruling opened the door for carbon dioxide to be regulated as a pollutant under the Clean Air Act. As a result, almost no coal-fired power plants are being built in the U.S., Gelsi said.

On a positive note, Gelsi says coal continues to be big in parts of the world with less stringent environmental rules. The annual energy study released by BP called coal “the fastest growing fossil fuel worldwide,” accounting for 33 percent of global energy consumption, the highest share since 1969.